According to legal documents obtained by the Los Angeles Times and TMZ Sports, Kelli Tennant, a former USC volleyball player, filed a lawsuit Monday in Los Angeles Superior Court and alleged that Walton assaulted her at the Casa Del Mar Hotel in Santa Monica, Calif.
No date was provided for the alleged assault, but the lawsuit said it happened after the publication of a book written by Tennant, who was a former Spectrum SportsNet LA host. The book, for which Walton wrote a foreword, was published in 2014.
The suit alleges that Tennant, who had a working relationship with the coach while he was a guest analyst on Spectrum, met with Walton at the hotel to drop off a copy of her book when he was in town on a road trip during his time as an assistant coach with the Golden State Warriors.
According to the Los Angeles Times, Walton allegedly invited Tennant to his room to avoid the public eye. He then allegedly "pinned Ms. Tennant on the bed, placing his hips and legs over her body" and forcibly kissed and groped her.
"Luke Walton retained me to defend him against these baseless allegations," Walton's attorney, Mark Baute, said in a statement. "The accuser is an opportunist, not a victim, and her claim is not credible. We intend to prove this in a courtroom."
Walton played for the Lakers from 2003 to 2012. After he retired as an NBA player, he entered broadcasting and appeared on Spectrum with Tennant. Walton eventually went into coaching and was on the Warriors' staff from 2014-16 until the Lakers hired him to be their next head coach.
Los Angeles released a statement Monday and noted that the alleged incident occurred before the franchise hired him.
"At no time before or during his employment here was this allegation reported to the Lakers," the statement said. "If it had been, we would have immediately commenced an investigation and notified the NBA. Since Luke Walton is now under contract to another team, we will have no further comment."
Walton led the Lakers for three seasons until the sides mutually parted ways April 12. He later became head coach of the Kings two days later.
"We are aware of the report and are gathering additional information," the Kings said in a statement. "We have no further comment at this time."
Tennant's lawyer, Garo Mardirossian, declined to disclose whether Tennant reported the alleged sexual assault to police, according to the Los Angeles Times.
The NBA has opened an investigation into the allegations against Walton, according to ESPN.